As said, tens of thousands of people are self-hosting *today*. Fediverse software doesn't just scale up, it scales *down*.
GotoSocial is cheap enough on resources where you can run it for family and friends on a raspberry pi or spare laptop you have sitting around.
Now you're hitting the point in this thread where some of you may be thinking "aha! this is where Christine is saying that the fediverse/activitypub are awesome and atproto is terrible!"
you have NO IDEA HOW MUCH I CRITICIZE THE FEDIVERSE ALL THE TIME, I do it all the time, and will later here